Here is your short essay on Tidal power

The tides in the sea are the result of the universal gravitational effect of Sun and moon on the earth. Due to fluidity of water mass, the effect of these forces becomes apparent in the motion of water. We see the periodic rise and fall in levels, which is in rhythm with a daily cycle of rising and setting of sun and moon.

This periodic rise and fall of water level of sea is called tide. A lot of energy is inherent in the twice-a-day rise and fall of the tides. These tides can be used to generate electricity, which is known as tidal power. When the water is above the sea level, it is called flood tide and when the level is below the mean sea level, it is called epp tide.

To harness the tides, a dam would be built, across the mouth of the bay. It will have large gate in it. A reversible water turbine is fitted into the dam. A tidal basin is formed which separated from a sea by the dam.

The difference in water level is obtained between the basin seas. The constructed basin is filled during high tides and empty during low tide passing the sluices turbine respectively. Due to that, the turbine runs and generates power.

There are two main types of tidal power generation schemes, viz., single basin scheme and double basin schemes.

(i) Single Basin Scheme: This scheme has one barrage and one water storage basin, one way system, the incoming tide is allowed to fill the basin through sluice ways during the tide and the impounded water is used to generate electricity by letting the water flow from basin to the sea through the turbines during single basin schemes is intermittent generation power.

(ii) Double Basin Scheme: In the double basin scheme, there are two basins on the landward side with the powerhouse located at the interconnecting waterway between the two basins; high basin is filled during the flood tide and low basin emptied during epp tide. Power is generate when water flows from the high basin to low basin and also when water flows from the basin to the sea during epp tide. This scheme provides a continuous output.

Some of the important power plants are:

(i) La Rance estuary in France.

(ii) Severn Estuary & Mersey Estuary in U.K.

(iii) San Jose Gulf in Argentina.

(iv) Cook Inlet in Alaska.

(v) Puget sound in Washington.

(vi) Bay of Fundy in Novascotia.

(vii) Gulf of Kutch and Gulf of Cambay in India.